Particles don't render
Look in the outliner window to make sure the camera icon switch for the particle object is enabled and bright.  This means render the object.

It is quite possible to see the particles in view mode and no particles in render for exactly this reason.  You may place your object particle in a different layer to keep it handy and out of camera view except in its role as a particle.

Look in modifiers panel to see if modifier is enabled in render mode.
The area has the eye , then arrow, then camera for each object.

In Render Layers panel, section Layer, verify the scene and layers include your desired results.



Verify your [global] coordinate selection for the particle system object particle suit your intended purpose and the location is not modified by render only modifiers.  Are your particles moved off viewport?

(I used casual explanation and names as per the user interface)

As always I may say something you may already know or have tested.